It is known to remotely control locomotives in a rail yard using remote radio transmitting devices controlled by rail yard personnel. Such remote control systems may include an operator control unit (OCU) or control tower unit in remote communication with a locomotive control unit (LCU) disposed onboard the locomotive. The LCU interfaces with known locomotive systems, such as locomotive traction control systems, and pneumatic train braking systems, to direct the locomotive to move and stop according to transmitted commands. For example, the LCU may provide commands to an automatic braking system for controlling braking of the locomotive (and any other locomotive or rail cars pneumatically attached to the locomotive) by modulating an air pressure in a brake pipe. The LCU may also provide commands to an independent braking system for controlling braking of the locomotive, independently of the automatic system, by modulating an air pressure in a locomotive pipe. In addition, the LCU may command a “bail” capability to control automatic braking of the locomotive independently of automatic braking applied to the rest of the train.
Under certain conditions, such as when the LCU detects a system fault, the LCU may automatically control operation of the locomotive until the fault is corrected. For example, the LCU may automatically stop movement of the locomotive by activating train braking systems when a certain fault is detected.